Composition and method for friction loss reduction

ABSTRACT

A catalyst and method is provided for the production of ultra-high molecular weight polymers characterized as having an inherent viscosity of above 12.0 by contacting ethylenically unsaturated monomers with a dual electron donor catalyst under polymerization conditions.

This is a division of application Ser. No. 271,552 filed Nov. 14, 1988and now U.S. Pat. No. 4,945,142.

SUMMARY OF THE INVENTION

Polymerization catalysts are prepared according to a set procedure toincrease inherent viscosity in polymers produced using such catalysts.In addition, the polymers are preferably produced in S a solutionpolymerization system for direct injection into a hydrocarbon flowingthrough a conduit.

This invention relates to a catalyst and method for the production ofultra-high molecular weight polymers. Such materials are suitable foruse as drag reducing agents in hydrocarbons flowing through conduits.More particularly, the present invention provides a catalyst and methodfor the production of ultra-high molecular weight polymers characterizedas having an inherent viscosity higher than 12.0 which provide extremelyeffective drag reduction.

It has long been known that alpha-olefins may be polymerized in thepresence of a catalyst system generally referred to as Ziegler-Nattacatalysts. These catalysts generally consist of materials such as atitanium trihalide and organometallic co-catalysts such as aluminumalkyls or aluminum halides as represented by triethylaluminum anddiethylaluminum halide.

There has been an extremely large amount of work carried out modifyingZiegler-Natta polymerizations with the aim of developing more efficientpromoters for the production of polymers, especially highly crystallinepolypropylene and poly(butene-1).

The present invention is directed toward production of highlynon-crystalline, hydrocarbon-soluble, very high (or ultra-high)molecular weight polymers primarily suitable as materials for reducingthe frictional drag of hydrocarbon fluids flowing through conduits. Suchpolymers are not useable for production of films, blow-molded or shapedartifacts.

With the increasing emphasis on production of hydrocarbons in variousremote locations of the world as more easily recoverable reservoirs aredepleted, it has become necessary to develop transportation systems fromsuch remote producing sources. Such transportation systems havetraditionally been pipelines. Pipelines require pumping stations spacedperiodically along the pipeline to move hydrocarbon fluids rapidly andefficiently to their destination. However, such fluids vary greatly inviscosity and often are heavily temperature dependent before economicaltransportation by pipeline can be achieved.

One solution to the necessity for adding additional pump stations isconstructing over-sized pipelines. Such over-sized pipelines requireadditional construction costs. Since petroleum-producing fields will bedepleted at a future time, it is more economical to add a drag reducingmaterial to the hydrocarbon fluid in order to reduce the frictional lossof the hydrocarbon flowing through the pipeline, rather than add to thecost of the pipeline by adding additional pump stations or increase thepipeline size.

U.S. Pat. No. 3,692,675 teaches a method for reducing friction loss ordrag for pumpable fluids through pipelines by adding a minor amount of avery high molecular weight polymers. Amounts of from about 5 to about500 parts per million of polyalpha-olefins in the pumpable fluid havebeen shown to provide drag reduction. The percent drag reduction forhydrocarbons being transported through a pipeline was defined in thispatent as ##EQU1## Polymers prepared from C₈ to C₁₀ alphamonoolefinswere found to be the most effective studied. It was further demonstratedthat higher molecular weight polymers, as measured by the acceptedcriteria of the polymers inherent viscosity, were more effective thanpolymers possessing low inherent viscosities and lower molecularweights.

Early attempts at utilizing polymers for such purposes involve polymershaving relatively low inherent viscosities and molecular weights. Themolecular weights were variously described as being between 1 and 10million and were not measured directly, but rather indirectly, via theinherent viscosity method.

It was also discovered as disclosed in U.S. Pat. Nos. 4,415,714 and4,493,904 that addition of an electron donor material to the basictransition metal halide and aluminum alkyl co-catalysts of aZiegler-Natta system, provided enhanced activity, which in turn allowedpolymerizations to be carried out at lower temperatures. Thispolymerization at lower temperature was found to increase the inherentviscosity (molecular weight) and provide a more effective drag reducingmaterial. The inherent viscosities of the materials prepared by thesemethods ranged to nearly 10.0, indicating a very high molecular weightproduct.

An improvement was set forth in U.S. Pat. No. 4,358,572, wherein it wasdiscovered that a pre-reaction of a transition metal halide togetherwith an ether prior to completing the catalyst preparation allowed thepreparation of a polymer having inherent viscosities of up to 11.5 whenpolymerization was ceased at a polymer content of 20 percent by weightor less.

However, it would be beneficial to provide a method and a polymer ofextremely high molecular weight which can be prepared under economicalconditions, in order to even further enhance the reduction of drag inhydrocarbon fluids flowing through pipelines.

We have now discovered catalysts capable of forming ultra-high molecularweight polymers characterized by an inherent viscosity above 12.0, andwhich produce from ethylenically unsaturated monomers a hydrocarbonsoluble, non-crystalline polymer capable of reducing drag inhydrocarbons flowing through conduits. In a preferred embodiment,teachings of the prior art could be utilized in conjunction with thepresent invention to even further improve the efficiency and theinherent viscosity of the materials produced.

THE PRIOR ART

The body of prior art relating to Ziegler-Natta catalysis is extremelylarge. However, representative, but non-exhaustive examples of patentsshowing catalyst systems include U.S. Pat. No. 3,408,340 in whichdialkylpolysiloxanes or the like used in certain proportions in an inertsolvent in order to increase catalyst reaction rate.

U.S. Pat. No. 4,358,572 shows a method of increasing inherent viscosityin drag reducing materials by utilizing ether-activating agent with atransition metal halide prior to combination with the Ziegler-Nattaco-catalyst.

U.S. Pat. No. 4.420.593 utilizes electron donors and acceptors at anytime during the reaction mixtures of ether and polysiloxanes arespecifically shown. Polymers produced are stereo regular polymers from aslurry polymerization system. Polymers produced were likewisecrystalline.

THE PRESENT INVENTION

The present invention utilizes a novel catalyst system which is preparedin a specified manner to provide a polymer having an inherent viscosityof at least 12.0. The system allows for increased reaction rates toobtain polymers having conventional inherent viscosities, i.e. below12.0 at extremely fast reaction rates and nearly ambient temperatures,but allows the production of extremely high IV materials forcommercially feasible reaction times at lower temperatures.

Therefore, an object of the present invention is to provide an improvedcatalyst and method for the polymerization of ethylenically unsaturatedmonomers to produce and high molecular weight polymer characterized ashaving an inherent viscosity greater than 12.0 by utilizing a catalystmodification which results in a higher inherent viscosity in theproduced polymers. Other objects will become apparent to those skilledin the art as the description proceeds.

We have now found in accordance with the present invention thatultra-high molecular weight, non-crystalline hydrocarbon solublepolymers characterized as having an inherent viscosity above 12.0 can beproduced utilizing a catalyst comprising:

(1) a transition metal halide of the general formula MX_(t) wherein M istitanium or vanadium, and t is equal to 2.0 to 4.0, and X is a halogen;

(2) at least one first electron donor selected from the group consistingof ethers, esters, amines, phosphines, piperidines, phosphites,phosphates, pyridines, sulfides and mixtures of these;

(3) a co-catalyst comprising an organoaluminum or organoaluminum halideof the formula AlR_(n) X_(3-n), wherein R is a hydrocarbon radicalcontaining from 1 to 20 carbon atoms, X is at least one constituentselected from the group consisting of halogen. siloxide or alkoxide, andn is less than 3.0; and

(4) a polysiloxane second electron donor having the general formula##EQU2## wherein R is hydrogen an alkyl group containing from 1 to 20carbon atoms, an aralkyl or alkaryl group containing from 6 to 20 carbonatoms, a and b are greater than 0, where the sum of a+b does not exceed3, and c is 2 or more.

We have discovered that the use of a non-silicon containing electrondonor and a polysiloxane under the mixing order and conditions describedhave a synergistic effect as illustrated in the experimental examplesset forth hereafter.

Further, the present invention comprises a method of forming anultra-high molecular weight polymer by first pre-reacting the firstelectron donor with the transaction metal compound before completing thecatalyst preparation. The catalysts are prepared under an inertanhydrous atmosphere. The catalysts are prepared by combining atransaction metal halide with an electron donor selected from the groupconsisting of ethers, esters, amines, phosphines, piperidines,phosphites, phosphates, pyridines, sulfides or mixtures of these, andallowing the components to react for at least 3, preferably 5 minutes.The co-catalyst and polysiloxane are added to complete the catalyst.More specifically, the method comprises:

(1) combining a transition metal halide of the general formula MX_(t)wherein M is titanium or vanadium, and t is equal to 2.0 to 4.0, and Xis a halogen with,

(2) at least 1 first electron donor selected from the group consistingof ethers, esters, amines, phosphines, piperidines, phosphites,phosphates, pyridines, and sulfides and allowing the components to reactfor a period of at least 3 minutes,

(3) then contacting the reaction product of (1) with (2), with aco-catalyst comprising an organoaluminum or organoaluminum halide of theformula AlR_(n) X_(3-n), wherein R is a hydrocarbon radical containingfrom 1 to 20 carbon atoms, X is at least one constituent selected fromthe group consisting of halogen, siloxide, or alkoxide and n is lessthan 3.0, and

(4) combining the resulting material with a polysiloxane second electrondonor having the general formula ##EQU3## wherein R is hydrogen, analkyl group containing from 1 to 20 carbon atoms, an aralkyl or alkarylgroup containing from 6 to 20 carbon atoms, a and b are greater than 0,and where the sum of a and b does not exceed 3, and c is 2 or more.

Once prepared, the catalyst is contacted with at least one alpha-olefincontaining from 2 to 20 carbon atoms, and where at least 40 mole percentof the olefins in contact with the catalyst are C₆ and larger incarrying out the polymerization.

The polymerization is carried out under standard polymerizationconditions. Normally, such reactions are carried out at temperaturesfrom -25° C. to about 80° C. and ambient pressure. Pressures higher orlower than ambient can be used. It is simply more convenient to carryout the reaction at ambient pressure. Polymerizations can be carried outto extreme or complete polymerization but normally are carried out for aspecified length of time, at which time total polymerization may nothave occurred.

It is preferred, but not critical, that polymerization be ceased at alevel below 20 percent by weight and that the temperatures utilized beas low as possible in order to maximize inherent viscosities. However,the catalysts of the present invention will provide higher inherentviscosities than known catalysts when compared under the samepolymerization conditions.

Ethylenically unsaturated monomers suitable for use in the presentinvention include alpha-olefins containing from 2 to 20 carbon atoms.Representative but non-exhaustive examples of such olefins includeethylene, propylene, butene-1, pentene-1, 4-methylpentene, octene-1,dodecene-1, decene-1, hexene-1, and octadecene-1. These olefins can beused alone. They can also be utilized with other ethylenicallyunsaturated monomers such as butadiene, pentadiene, styrene, isoprene,alpha-methylstyrene, and the like. However, for purposes of promotingdrag reduction in hydrocarbons flowing through conduit, it is preferredthat at least 20 weight percent of the resultant polymer is formed fromalpha-olefins containing at least 4 carbon atoms. It is most preferredthat the polymer is dissolved in the hydrocarbon.

Preferably, the polysiloxane utilized in the catalyst is ahydropolysiloxane having an a value of from 0.1 to 2, a b value of 1, 2or 3, and wherein the sum of a and b does not exceed 3. In a mostpreferred embodiment, the transition metal halide and diethyl etherfirst modifier are allowed to react for at least 3 minutes andpreferably 5 minutes, before completing the catalyst preparation.Allowing such reaction time provides an increase in inherent viscosity.

The catalyst can be prepared as a slurry, using a hydrocarbon diluent.These materials are inactive hydrocarbon solvents with respect to thepolymerization. Examples of such materials are straight chain aliphaticcompounds or branched hydrocarbons such as ethane, propane, butane,pentane, hexane, heptane or octane. Also suitable are alicyclichydrocarbons such as cyclohexane, methyl cyclopentane and tetralin. Inaddition, aromatic hydrocarbons can be used such as benzene, toluene,and xylene. 0f course, mixtures and analogues of these compounds can beused such as Molex (trademark of Universal Oil Products) raffinate whichis a complex mixture of branched aliphatic, cyclic aliphatic, aromatic,and trace amounts (2-3%) of unbranched aliphatic hydrocarbons. Thehydrocarbon diluent can also be an α-olefin.

It is preferred to use a hydrocarbon which is a good solvent for thepolymer and which also boils at a temperature much higher than thepolymerization temperature so that polymerization can be carried out atatmospheric pressure.

Of course, utilizing hydrocarbons which solubilize the produced polymersresults in a solution polymerization and such polymerizations arepreferred. Solution polymerizations are preferred since the resultantreactor product can be utilized as produced without the necessity ofisolating the drag reducing polymer. Also, if the polymer is already insolution, it is easier to dissolve the polymer in a hydrocarbon fluidflowing through a conduit and obtain a homogenous solution. Theresultant solution can be injected directly into hydrocarbon fluidsflowing through conduits and the dissolution of the polymer in thehydrocarbon. Normally, such solution polymerizations will contain from 1to 20 percent by weight polymer, but of course higher concentration canbe formed. As described in the prior are, however, the higher theconcentration of polymer, the lower the overall average inherentviscosity.

Catalyst modifiers are materials which activate the catalyst whileallowing the catalyst to remain in the form of a finely divided slurry.In the present invention, these activating catalyst modifiers are weakto moderately strong Lewis bases, as defined in Advanced OrganicChemistry: Reactions. Mechanisms, and Structures. March, J, McGraw-HillBook Company, 1968, page 227. Concisely stated, a Lewis base is acompound with an available pair of electrons either unshared or in a πorbital. These materials are catalyst poisons (or deactivators) whenpresent in larger quantities. Conversely, this same Lewis basicity whichpoisons the catalyst must be present in a lesser activating amount,since the total absence of Lewis base provides no enhanced activity andsimply dilutes the catalyst.

Representative but non-exhaustive examples of such modifying agents areethers, amines, phosphines, piperidines, phosphites, phosphates,pyridines, esters and sulfides. Of these, ethers and amines arepreferred activating agents, since better activity is found and thecatalyst is less sensitive to deactivation.

Ether activators are selected from alkyl ethers where ether oxygen isattached directly to two aliphatic groups and may have aromaticsubstituents; aryl ethers wherein the ether oxygen is attached directlyto two aromatic groups; aryl alkyl ethers wherein the ether oxygen isattached directly to one aliphatic and one aromatic group; and cyclicethers wherein the ether oxygen is an integral part of a ring structure.The ether can therefore contain alkyl, aryl, aryl alkyl, or alkyl arylgroups, each containing from 2 to 30 carbon atoms. These materials canbe used at modifier to titanium molar ratios of up to 10.0.

Representative but non-exhaustive examples of alkyl ethers are dimethylether, benzyl ether, tert-butyl methyl ether, di-n-butyl ether,diisopropyl ether, and di-n-propyl ether. Representative examples ofcyclic ethers are cyclododecene oxide, cyclohexene oxide, cycloocteneoxide, cyclopentene oxide, dibenzylfuran, dihydropyran, furan,2-methylfuran, 3-methylfuran, 2-methyltetrahydrofuran,3-methyltetrahydrofuran, styrene oxide, and tetrahydrofuran.Representative examples of aryl ethers are m-phenoxytoluene and phenylether. Representative examples of aryl alkyl ethers are anisole, butylphenyl ether, m-dimethoxybenzene, p-dimethoxybenzene,2,6-dimethoxytoluene, 1-methoxynaphthalene, and 2-methoxynaphthalene.

Representative but non-exhaustive examples of amines useful in thepresent invention are tri-n-butyl amine, diisopropyl ethyl amine,dibutyl amine, trimethyl amine, tri-n-propyl amine, tri-i-propyl amine,tribenzyl amine, tri(4-methyl phenyl) amine, triphenyl amine, dimethylphenyl amine, di-sec-butyl benzyl amine, ethyl propyl phenyl amine,diisopropyl ethyl amine, diisopropyl amine, di-n-butyl amine, dibenzylamine, diphenyl amine, benzyl methyl amine, benzyl phenyl amine, andn-butyl-i-propyl amine. These amines can be used in amine to titaniummole ratios of up to 5.0.

Representative but non-exhaustive examples of phosphines useful in thepractice of the present invention are tributyl phosphine, trioctylphosphine, trimethyl phosphine, triphenyl phosphine, dibenzyl phenylphosphine, diphenyl butyl phosphine, dioctyl benzyl phosphine, dihexylmethyl phosphine, di-cyclo-pentyl ethyl phosphine, hexyl methyl-i-propylphosphine, and ethyl(2-phenyl ethyl)phenyl phosphine. These phosphinescan be used in phosphine to titanium mole ratios of up to 3.0.

Representative but non-exhaustive examples of phosphates useful in thepractice of the invention are tributyl phosphate, dimethyl octylphosphate, diphenyl propyl phosphate, di-s-butyl benzyl phosphate,trioctyl phosphate, tribenzyl phosphate, and decyl ethyl phenylphosphate. These phosphates can be used in phosphate to titanium moleratios of up to 3.0.

Representative but non-exhaustive examples of piperidines useful in thepractice of the present invention are 2,2,6,6-tetramethyl piperidine,3,3,5,5-tetraethyl piperidine, 2,2,6-tri-n-butyl piperidine.2,6-diphenyl-2,6-dimethyl piperidine, 2,6-dibenzyl-2,6-diethylpiperidine, 2,6-dioctyl piperidine, and 2,6-diphenyl piperidine. Thesepiperidines can be used in piperidine to titanium mole ratios of up to3.0.

Representative but non-exhaustive examples of sulfides useful in thepractice of the present invention are n-hexyl sulfide n-butyl sulfide,sec-butyl sulfide, n-decyl sulfide, di(2-phenyl propyl)sulfide,phenyl-i-octyl sulfide, benzyl methyl sulfide, phenyl sulfide, and(4-methyl phenyl)sulfide. These sulfides can be used in sulfide totitanium mole ratios of up to 3.0.

Representative but non-exhaustive examples of phosphites useful in thepractice of the present invention are tri-n-propyl phosphite,tri-n-butyl phosphite, tri-i-octyl phosphite, di-s-butyl-n-decylphosphite, dibenzyl-n-hexyl phosphite, diphenyl-i-heptyl phosphite,diethyl phenyl phosphite, benzyl methyl phenyl phosphite, andcyclo-pentyl ethyl octyl phosphite. These phosphites can be used inphosphite to titanium mole ratios of up to 3.0.

Representative but non-exhaustive examples of hydropolysiloxanes usefulin the practice of the present invention are polymethylhydrosiloxane(PMHS), polyethylhydrosiloxane, polyethoxyhydrosiloxane,polymethylhydro-dimethylsiloxane copolymer,polymethylhydromethyloctylsiloxane copolymer, polyethoxyhydrosiloxane,tetramethyldisiloxane, diphenyldisiloxane, trimethylcyclotrisiloxane.tetramethylcyclotetrasiloxane, polyphenylhydrosiloxane,polyeicosylhydrosiloxane, polychlorophenylhydrosiloxane, and mixtures ofthese. The polysiloxanes can be used in polysiloxane to titanium moleratios of up to 40.0.

Representative but non-exhaustive examples of silicon compounds whichare useful in the present invention are trimethylhydroxysilane,triethylhydroxysilane, triphenylhydroxysilane,methyldiphenylhydroxysilane, benzyldiphenylhydroxysilane,diethyldihydroxysilane, dipropyldihydroxysilane, addition siloxaneswhich are terminated with other groups, such as hydride, amino andcarbinol may be used. Also useful are siloxanes which do not containterminal functional groups.

The polymers may be diluted with a solvent prior to combining them withthe hydrocarbon liquid portion of the reduced friction losscompositions. Suitable solvents include kerosene, naphtha and otherpetroleum distillates and saturated hydrocarbons such as hexane,heptane, octane, etc. While other methods of introduction may beemployed the polymers can conveniently be added to the hydrocarbonliquid by continuous injection into the carrier conduit by means ofproportionating pumps situated at desired locations along the conduit.

The following examples are presented in illustration of specificembodiments of the invention.

The instant invention is more concretely described with reference to theexamples below, wherein all parts and percentages are by weight unlessotherwise specified. The examples are provided to illustrated thepresent invention and not to limit it.

EXPERIMENTAL PROCEDURE

In the experiments which follow, a one-quart, narrow-mouthedbeverage-type bottle was washed with soap and water solution and anorganic solvent, such as isopropenol, hexane or acetone. The bottle wasthen rinsed thoroughly with the ionized water, dried for at least 48hours in an oven at 100° to 140° C., and cooled to room temperature in avacuum.

The dry bottle was taken into a glove box containing a nitrogenatmosphere, having less than 10 parts per million water and oxygen.Decene-1 (60.5 milliliter) was diluted to a total volume of 500milliliter with MRTM solvent (trademark of Vista Chemical Co.), and thissolution was added quantitatively to the bottle. The liquid olefin andsolvent had been nitrogen purged and passed through a bed of molecularsieves and silica gel prior to use. MRTM solvent is an aliphatichydrocarbon having a molecular weight range similar to that of kerosene.

The bottle was then capped with a rubber septum removed from the glovebox and placed in a shaker bath at 0° C. The bottle was equilibrated tothe bath temperature. An aliquot of catalyst slurry was then transferredfrom the septum capped 125 milliliter (ml) bottle to a polymerizationbottle using a nitrogen-purged syringe. The polymerization bottle wasagitated, as necessary, to keep the catalyst slurry suspended. After 24hours at 0° C., the polymerization was terminated by mixing 5 ml of akill solution with a polymerization mixture. The kill solution used wasa 4 weight percent solution of Vanlube® XL in an hexanol. Vanlube® XL isa registered trademark of and the material was obtained from the R. T.Vanderbilt Co., Inc.

Weight percent polymer was determined gravimetrically by precipitatingthe polymer from solution with isopropenol. The inherent viscositieswere determined according to the Cannon-Ubbelhold 4-bulb viscometermethod.

EXAMPLES 1 THROUGH 3

The teachings of U.S. Pat. No. 4,358,572 were experimentally repeatedexcept that dibutylaluminumchloride was utilized instead ofdiethylaluminum chloride (DEAC). In these experiments, 20 ml of TiCl₃ AAwas combined with 8 ml of 0.5 molar dibutylether (DBE), each providing4.0 millimoles to the mixture. The mixture was stirred 5 minutes withthe reaction bottle capped. After the 5 minute stirring, 15.4 ml of 1.05molar dibutylaluminum chloride (16.0 millimoles) was added together with56.6 ml of hexane to form a total volume of 100 ml. Aliquots of thiscatalysts were added to each of 3 reaction bottles and hexene was added.Polymerizations were carried out for 24 hours at 0° C. at which timereactor contents inherent viscosity were measured. The results are setforth in Examples 1, 2 and 3 of Table 1.

EXAMPLES 4 THROUGH 9

A reaction was carried out as described in Examples 1-3, except thatpolymethylmethylsiloxane (PMMS) was utilized in place of dibutyl ether.A catalyst was prepared by adding 10 ml of 0.2 molar TiCl₃ AA containing1.9955 millimoles titanium with 7.6 ml of 1.05 molar DIBAC(dibutylaluminum chloride) containing 7.982 millimoles of activematerial. To this mixture was added 2.0 ml of 2.00 molar PMMS containingcontaining 3.999 millimoles active material. 30.4 ml of hexane wasadded. The catalyst contained a co-catalyst to titanium ratio of 4 and aPMMS to DIBAC ratio of 0.5. Additional experiments were run, such thatExperiment 5 had a PMMS to DIBAC ratio of 1.0. Experiment 6 had a PMMSto DIBAC ratio of 2.0, Experiment 7 had a PMMS to DIBAC ratio of 10.0,Experiment 8 had a PMMS/DIBAC ratio of 0.25, and Experiment 9 was acontrol having a PMMS ratio to DIBAC of 0 (no PMMS was added). Theresults are set forth in Table 1 as Experiments 4-9.

EXAMPLES 10 THROUGH 15

Experiments were carried out utilizing various catalyst preparations. InExperiments 10 and 11, the catalyst was formed by combining 10 ml of0.20 molar TiCl₃ AA (2.0 millimoles titanium) with 4.0 of 0.5 molardibutylether (2.0 millimoles). The mixture was stirred 5 minutes withthe bottle capped. After the mixture had stirred, 7.7 ml of 1.05 molardibutylaluminum chloride (7.98 millimoles) was added and the bottle wasstirred an additional 5 minutes. After this stirring, 1.0 milliliters of2.0 molar PMMS (2.0 millimoles PMMS) was added together with 27.3 ml ofhexane. The catalyst of a co-catalyst to titanium ratio of 4, adibutylether to titanium ratio of 1, and a PMMS/titanium of 1.0.

A second catalyst was prepared in the same fashion as described aboveexcept that dibutylether and diisobutylaluminum chloride (DIBAC) wereadded to the TiCl₃ AA and the entire mixture was stirred for 5 minuteswith the bottle capped prior to the addition of PMMS. The catalystratios were the same.

A catalyst was prepared in a different fashion such that dibutyletherwas stirred for 5 minutes with TiCl₃ AA whereafter dibutylaluminumchloride and PMMS were added to form this catalyst having the same ratioas first described.

Duplicate polymerizations were carried out utilizing the catalystsdescribed, such that Experiments 10 and 11 were formed with catalysts 1;12 and 13 were formed with catalyst 2; and 14 and 15 were carried outwith catalyst 3. The results are set forth in Table 1.

EXAMPLES 16-18

A catalyst was prepared by mixing 100 ml of 0.2 molar TiCl₃ AA and ml of0.5 molar dibutylether in an 8 ounce narrow-mouthed bottle with amagnetic stir bar. The solution was stirred under an inert atmospherefor at least 5 minutes prior to using.

From catalyst 1, 14.0 ml of the slurry was combined with 3.8 ml of 1.05ml molar DIBAC and stirred 5 minutes with the bottle capped. Afterstirring, 1.0 ml of 2.0 molar PMMS (2.0 millimoles PMMS) was added,together with 31. 2 ml of hexane. The co-catalyst at titanium ratio was2, the dibutylether to titanium ratio was 1, and the PMMS to titaniumratio was 1 for Example 16.

A second catalyst was prepared exactly as described, except that 7.7 mlof 1.0 molar DIBAC (8.0 millimoles) was added for Example 1.

A third catalyst was prepared, except that 15. 2 ml of 1.05 molar DIBACwas added (16.0 millimoles) for Example 18.

Polymerization were carried out with the catalyst described. The resultsare set forth in Examples 16-18 of Table 1.

                                      TABLE 1                                     __________________________________________________________________________    SUMMARY OF POLYMERIZATION DATA                                                                     Reactor                                                                       Content                                                                       %    Inherent                                                                           Olefin/Ti                                      Example                                                                            Catalyst Preparation                                                                          Polymer                                                                            Viscosity                                                                          Ratio                                          __________________________________________________________________________     1   1 TiCl.sub.3 AA/DBE/DIBAC                                                                     7.51 16.5 400                                             2   2 TiCl.sub.3 AA/DBE/DIBAC                                                                     8.08 15.8 400                                             3   3 TiCl.sub.3 AA/DBE/DIBAC                                                                     8.45 15.8 400                                             4   TiCl.sub.3 AA/DIBAC/PMMS                                                                      3.21 17.3 400                                             5   TiCl.sub.3 AA/DIBAC/PMMS                                                                      3.03 16.8 400                                             6   TiCl.sub.3 AA/DIBAC/PMMS                                                                      3.68 16.9 400                                             7   TiCl.sub.3 AA/DIBAC/PMMS                                                                      1.23 16.7 400                                             8   TiCl.sub.3 AA/DIBAC/PMMS                                                                      3.82 15.9 400                                             9   TiCl.sub.3 AA/DIBAC                                                                           2.90 15.5 400                                            10   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  9.10 16.3 400                                            11   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  9.88 16.2 400                                            12   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  9.23 16.3 400                                            13   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  9.30 16.1 400                                            14   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  9.06 16.7 400                                            15   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  8.88 16.7 400                                            16   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  5.27 17.0 800                                            17   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  4.93 17.2 800                                            18   TiCl.sub.3 AA/DBE/DIBAC/PMMS                                                                  4.44 17.2 800                                            __________________________________________________________________________

It can be seen from Table 1 that utilization of the dual electron donorsystem of the present invention provides an increase in the reactionrate relative to an inherent viscosity (that is, that inherentviscosities of the level previously obtained can be obtained at a higherreactor polymer content). It can also be seen from Examples 16-18 thatwhen amount of polymer is sacrificed by lowering the proportion ofcatalyst activity components, that even higher inherent viscosities canbe routinely obtained. The present invention thus provides a specificcatalyst for increasing that inherent viscosity of produced polymer, orin the alternative, providing a much higher rate of obtaining polymer atlower inherent viscosities.

While certain embodiments and details have been shown for the purpose ofillustrating the present invention, it will be apparent to those skilledin this art that various changes and modifications may be made hereinwithout departing from the spirit or scope of the invention.

We claim:
 1. A catalyst capable of forming ultrahigh molecular weightpolymers, as characterized by an inherent viscosity greater than 12.0,comprising:(1) a transition metal halide of the general formula MX_(t)wherein M is titanium or vanadium, and t is equal to 2.5 to 4.0, and Xis a halogen; (2) at least one first electron donor selected from thegroup consisting of ethers, esters, amines, phosphines, piperdines,phosphites, phosphates, pyridenes, sulfides and mixtures of these; (3) aco-catalyst comprising an organoaluminum or organoaluminum halide of theformula AlR_(n) X_(3-n), wherein R is a hydrocarbon radical containingfrom 1 to 20 carbon atoms, X is at least one constituent selected fromthe group consisting of halogen, siloxide or alkoxide, and n is lessthan 3.0; and (4) a polysiloxane second electron donor having thegeneral formula ##EQU4## wherein R is hydrogen an alkyl group containingfrom 1 to 20 carbon atoms, an aralkyl or alkaryl group containing from 6to 20 carbon atoms, a and b are greater than 0, where the sum of a+bdoes not exceed 3, and c is 2 or more.
 2. A catalyst as described inclaim 1 wherein the polysiloxane is a hydropolysiloxane, where a has avalue of from 0.1 to 2.0, b has a value of 1.0, 2.0 or 3.0, and whereinthe sum of (a+b) does not exceed
 3. 3. A catalyst as described in claim2 wherein the first electron donor compound is primarily an ethercompound containing alkyl, aryl, aryl alkyl, aryl alkyl, or alkyl arylgroups, each containing from 1 to 30 carbon atoms or cycloalkyl etherscontaining from 6 to 30 carbon atoms.
 4. A catalyst as described inclaim 3 wherein the ether is at least one ether selected from the groupconsisting of diethyl ether, benzyl ether, tert-butyl methyl ether,di-n-butyl ether, diisopropyl ether, di-n-propyl ether, cyclododeceneoxide, cyclohexene oxide, cyclooctene oxide, cyclopentene oxide,dibenzylfuran, dihydropyran, furan, 2-methylfuran, 3-methylfuran,2-methyltetrahydrofuran, 3-methyltetrahydrofuran, styrene oxide,tetrahydrofuran, m-phenoxytoluene, phenyl ether, anisole, butyl phenylether, m-dimethoxybenzene, p-dimethoxybenzene, 2,6-dimethoxytoluene,1-methoxynaphthalene, and 2-methoxynaphthalene.
 5. A catalyst asdescribed in claim 3 wherein the first electron donor is an amineselected from the group consisting of: tri-n-butyl amine, diisopropylethyl amine, dibutyl amine, trimethyl amine, tri-n-propyl amine,tri-i-propyl amine, tribenzyl amine, tri(4-methyl phenyl) amine,triphenyl amine, dimethyl phenyl amine, di-sec-butyl benzyl amine, ethylpropyl phenyl amine, diisopropyl ethyl amine, diisopropyl amine,di-n-butyl amine, dibenzyl amine, diphenyl amine, benzyl methyl amine,benzyl phenyl amine, and n-butyl-i-propyl amine.
 6. A method forpreparing a catalyst capable of forming ultra-high molecular weightpolymers as characterized by an inherent viscosity greater than 12.0,comprising combining under an inert substantially anhydrousatmosphere:(1) a transition metal halide of the general formula MX_(t)wherein M is titanium or vanadium, and t is equal to 2.5 to 4.0, and Xis a halogen, with (2) at least one first electron donor selected fromthe group consisting of ethers, esters, amines, phosphines, piperidines,phosphites, phosphates, pyridines, sulfides and mixtures of these, andallowing the components to react for a period of at least 3 minutes,then contacting the reaction production of (1) and (2) with (3) aco-catalyst comprising an organoaluminum or organoaluminum halide of theformula AlR_(n) X_(3-n), wherein R is a hydrocarbon radical containingfrom 1 to 20 carbon atoms, X is at least one constituent selected fromthe group consisting of halogen, siloxide, or alkoxide and n is lessthan 3.0, then combining (4) a polysiloxane second electron donor havingthe general formula ##EQU5## wherein R is hydrogen, an alkyl groupcontaining from 1 to 20 carbon atoms, an aralkyl or alkaryl groupcontaining from 6 to 20 carbon atoms, a and b are greater than 0, andwhere the sum of (a+b) does not exceed 3, and c is 2 or more.
 7. Amethod as described in claim 6 wherein transition metal halide and firstelectron donor are allowed to react for at least 5 minutes prior toadding the additional catalyst components.
 8. A method as described inclaim 7 wherein the first electron donor is selected from the groupconsisting of ethers and amines.
 9. A method as described in claim 6wherein the ether is at least one ether selected from the groupconsisting of: benzyl ether, tert-butyl methyl ether, di-n-butyl ether,diisopropyl ether, di-n-propyl ether, cyclododecene oxide, cyclohexeneoxide, cyclooctene oxide, cyclopentene oxide, dibenzylfuran,dihydropyran, furan, 2-methylfuran, 3-methylfuran,2-methyltetrahydrofuran, 3-methyltetrahydrofuran, styrene oxide,tetrahydrofuran, m-phenoxytoluene, phenyl ether, anisole, butyl phenylether, m-dimethoxybenzene, p-dimethoxybenzene, 2,6-dimethoxytoluene,1-methoxynaphthalene, and 2-methoxynaphthalene.
 10. A method asdescribed in claim 6 wherein the amines are selected from the groupconsisting of tri-n-butyl amine, diisopropyl ethyl amine, dibutyl amine,trimethyl amine, tri-n-propyl amine, tri-i-propyl aming, tribenzylamine, tri(4-methyl phenyl) amine, triphenyl amine, dimethyl phenylamine, di-sec-butyl benzyl amine, ethyl propyl phenyl amine, diisopropylethyl amine, diisopropyl amine, di-n-butyl amine, dibenzyl amine,diphenyl amine, benzyl methyl amine, benzyl phenyl amine, andn-butyl-i-propyl amine.